Cairo Montenotte sits on the A6 motorway between Savona and Turin — from Savona on the coast the drive takes about 30 minutes, and from Turin around an hour and a half. The town is also served by the Savona–Turin rail line, with regional trains running roughly every two hours. The station is a short walk from the town centre.
From Genoa, you'll need to change at Savona. The drive via the A10 and then the A6 takes about an hour. There is no direct public transport from the Ligurian Riviera towns; the easiest connection is via Savona or Carcare.